Israel has launched massive strikes against the southern suburbs of Beirut just hours after its military ordered the entire population of the area – more than 500,000 people – to evacuate the area immediately.

The Israel Defense Forces had told all residents of the area to “save your lives and evacuate your homes immediately”, prompting an exodus of the Lebanese capital’s population in scenes of panic, before its warplanes launched strikes against what it claimed were Hezbollah targets in the area. The area covered by the order included several hospitals and government ministries.

The strikes marked a significant escalation in Israel’s growing offensive in Lebanon, which began after Hezbollah fired missiles and drones into Israel on Monday.

Footage on Thursday evening showed smoke billowing over the neighbourhood of Dahiya. Israel’s far-right finance minister, Bezalel Smotrich, said that the strikes would make the Beirut suburb “look like [Gaza’s] Khan Younis,” a section of southern Gaza that has been almost entirely destroyed by Israeli bombs.

On the same day, Tehran launched retaliatory airstrikes against Israel and US bases across the region, and Pete Hegseth, the US defence secretary, promised a further escalation. “If you think you’ve seen something, just wait,” he said.

At the White House, Donald Trump said that members of the Islamic Revolutionary Guard Corps (IRGC) would be given immunity if they threw down their weapons, but otherwise would face “guaranteed death”. He said the offer for immunity extended to Iran’s military and the police.

Trump claimed he should be involved in choosing Iran’s next supreme leader to replace Ayatollah Ali Khamenei, who was killed in a US-Israeli airstrike on the first day of the war.

Trump said Mojtaba Khamenei, the 56-year-old son of the late supreme leader – the country’s head of state and commander-in-chief – would be an “unacceptable” choice.

“We want to be involved in the process of choosing the person who is going to lead Iran into the future,” Trump told Reuters. “We don’t have to go back every five years and do this again and again.”

Iran expanded its campaign of strikes, firing more ballistic missiles towards Israel, striking an airport in Azerbaijan, and raising fears that the conflict – now affecting 14 countries across the Middle East and beyond – could spread further.

The Israeli defence minister, Israel Katz, said on Thursday that the decision to assassinate Khamenei was made in November, far predating the breakdown in the nuclear programme negotiations that Donald Trump claimed led to the US launching a preemptive strike on Iran. The original timeline was for Israel to target Khamenei in the middle of 2026 but Netanyahu moved it up the schedule after riots broke out in Iran, Katz said.

The claim could bolster critics of Trump, who say that Israel had dragged the US into a large war in the Middle East with Iran. Secretary of state, Marco Rubio, said earlier that the US launched the strike on Iran because it expected to be targeted after the Israeli attack.

Katz has also said that Khamenei’s successors will be “unequivocal targets for elimination”.

Thursday’s sweeping evacuation order for southern Beirut was unprecedented in its scale: even during the 13-month war between Israel and Hezbollah in 2024, no evacuation order so broad was issued.

Traffic was at a standstill throughout the city and thousands of people resorted to walking, with women pushing strollers holding infants through bumper-to-bumper traffic. Families made appeals for rescue services to help extract elderly people who could not leave their homes on their own.

The Israeli military spokesperson provided pre-approved routes north and east which it said people should use to flee – a tactic reminiscent of evacuation orders Israel issued in Gaza.

At least 102 people have been killed and 638 injured in Lebanon by Israeli airstrikes, Lebanon’s ministry of health reported before Thursday night’s bombardment. The war, now in its sixth day, has also killed at least 1,230 people in Iran and about a dozen people in Israel. Six US soldiers have been killed.

The evacuation order was issued just a day after the Israeli military ordered all residents to flee the area south of the Litani River, which compromises about 10% of the country.

Israeli and Hezbollah soldiers were fighting in south Lebanon, according to UN peacekeepers in the area, as Israel continued its retaliatory campaign against the pro-Iran force that launched missiles into Israel on Monday.

The US and Israel continued their bombardment of Iran, hitting key ballistic missile launchers, weapons caches and security installations on Thursday.

Israel’s military also warned residents in eastern parts of Tehran to evacuate, while Iranian media reported blasts across the capital. “Today is worse than yesterday,” one resident of the city told Reuters. “We have nowhere to go. It is like a warzone. Help us.”

Sri Lanka said its navy had recovered at least 87 bodies after a US submarine sank an Iranian warship, IRIS Dena, on Wednesday. Thirty-two sailors were rescued out of a total crew of almost 130. The country reported that another Iranian ship had arrived in its waters, without reporting further details.

Iran’s foreign minister, Abbas Araghchi, reacted with fury to the US’s sinking of Dena, accusing it of carrying out an “atrocity of sea”. “Mark my words: The US will come to bitterly regret [the] precedent it has set,” Araghchi said in a post on X, while a senior Iranian cleric called for the exacting of “Trump’s blood” on state TV.

Iran’s retaliatory campaign of strikes has hit targets as far afield as Cyprus and created the world’s largest travel disruption since Covid as countries shut down their airspaces, and caused oil prices to spike.

Gulf countries reported more incoming Iranian projectiles throughout the day, which Iran said were targeted at US bases and personnel stationed there. A drone was shot down near Al Dhafra airbase in the United Arab Emirates, wounding six people when shrapnel fell. Qatar said there was a missile attack on the capital, Doha, and Saudi Arabia announced it had destroyed a drone. A tanker was attacked off the coast of Kuwait but it was unclear if the ship was damaged.

In Azerbaijan, a drone strike wounded four people near an airport in Nakhchivan, in an area bordering Iran, while another drone fell close to a school. Azerbaijan’s president, Ilham Aliyev, said Iran had committed a “groundless act of terror and aggression” and said the military was prepared to retaliate.

Tehran denied the claims, and the general staff of the Iranian armed forces denounced the allegations as baseless.

Iran also targeted the headquarters of Iranian Kurdish forces in northern Iraq as it increased its strikes on Kurdish forces in Iran and Iraq. The attacks came as the US and Israel pressed forward with an apparent plan to help thousands of Kurdish fighters to push into Iran as part of a ground operation.